DE1815244B2 - THERMAL AND ACID RESISTANT MINERAL FIBER PRODUCTS MADE FROM UBLE GLASS-FORMING OXIDES OR MINERALS, IN PARTICULAR NATURAL CLAYS AND IRON OXIDES, AND THE PROCESS FOR THEIR PRODUCTION - Google Patents

Description

Hus usual glass-forming oxides or minerals, in particular consist of natural clays and iron oxides and are characterized by a content of fusible iron oxides of at least 18 percent by weight but at most 35 percent by weight in addition to varying amounts of SiO ₂ and Al ₃ O ₃ , if necessary (customary admixtures, and a low content up to a maximum of 5 weight percent of alkaline earth and alkali metal oxides, based on the weight of the dried at 120 ⁰ C glass batch. in the Verwendug of alkali and / or alkaline earth oxides as fluxes can surprisingly entirely or largely be dispensed with if the content by weight of iron oxides, a sufficient Height and at least 18 percent by weight, based on the weight of the anhydrous mixture, It has proven to be expedient that the iron oxides in the starting mixture are predominantly in the form of Fe ₂ O ₃ and FeO, Fe ₂ O ₃ only in low concentrations, below about 5 weight per cent ozent, occurs. The weight ratio of Fe ₂ O ₃ to FeO is expediently always greater than 5: 1, a particularly favorable range being between 15: 1 and 25: 1.

The mineral wool proposed according to the invention is dun !; Pulling out or blowing a melt produced, the starting mixture of which is expediently composed so that, in addition to the glass-forming oxides known per se, they contain the required high proportion of iron oxides above 18 percent by weight, with particular advantage in proportions between 20 and 35 percent by weight and 15 to 65 percent by weight SiO ₂ and contain 33 to 12 weight percent Al ₂ O _3. In addition to these main components, customary admixtures such as TiO ₂ and MnO or the like can be present in the mixture in low concentrations of less than about 3 percent by weight. The usual alkali and / or alkaline earth oxides, which often have a detrimental effect on the quality of the end product, can be wholly or partially omitted and may not make up more than 5 percent by weight of the mixture.

Starting batch for the manufacture of mineral fiber products with the specified compositions can be produced by mixing the oxides in the required proportions. you will be but also useful from minerals with a suitable composition, e.g. B. from clays with or without Aggregates, won.

Exemplary for inventive mixture are

as the following compositions:

SiO ₂

Al ₂ O ₃

Fe ₂ O ₃

FeO

CaO + MgO

K ₂ O + Na ₂ O

TiO ₂

Loss on ignition and trace content

Melting temperature ...

Mixture according to the invention

Example 1 ! Example 2 Example 3

Weight percent j Gsv'chtsprozent weight percent

50
15th
18th

3.5
4th
1
8.5

1340 ° C

45
15th
25th

2.5

2.5

154O ⁰ C

40
13th
35

0.5

6.5

154O ⁰ C

Conventional

mixture
Weight percent

42.5

1
25.5

3.5

0.5
21

The batches of Examples 1, 2 and 3 show good melting behavior. Because of the small percentage of the alkaline earth oxides, the melt shows practically no tendency to crystallize. The viscosity of the Melt makes the mixture for the production of fiber products by methods known per se suitable.

The melt produced from a mixture composed according to the invention in the manner mentioned above can be processed into mineral wool by one of the nozzle drawing processes known per se or one of the blowing processes likewise known per se. This mineral wool is distinguished from a mineral wool produced from a known mixture by the same process, above all, by its increased heat resistance and its acid resistance. Under the same test conditions, the increase in the application limit temperature of mineral fiber products composed according to the invention is on average 200 to SCiO ⁰ C compared to known mixtures which contain alkaline earth metal oxides as fluxes. The increase compared to E-glass is even over 40O ⁰ C.

To test the acid resistance, 1 g of wool from each of the above-mentioned mixtures was refluxed for 5 minutes in 50 ml of normal HCl oil and then titrated with NaOH. In this test, a consumption of HCl between about 15 and 40 ml is found for the conventional mineral wool with alkaline earth oxides as the flux, while this consumption in the inventive clay wool according to Example 1 is 0.5 ml HCl and, in Example 3, 0.2 ml HCl. The consumption of HCI is a measure of the dissolution of the wool by acid.

A mineral wool, mineral fiber, mineral silk od . B. nozzle blowing process, centrifugal process, nozzle drawing process or the like. Manufacture.

The new composition not only results in new and advantageous properties mineral wool, especially heat and acid resistance, but also an improvement of the manufacturing process, which is also the subject of the invention. The improvement of the manufacturing process lies in the fact that one of a glass-forming

H the mixture runs out that contains high proportions of iron oxides, which replace the conventional flux in whole or in part, which may be contained in the mixture up to a maximum of 5 percent by weight,

.j

This results in the procedural progress that the usual crystallization difficulties during melting. The Fließveihallen the melt charges regulate derait by appropriate dosage of the iron oxides that with increasing content of iron oxides, in particular in the range of about 20 to 30 percent by weight, say on the dried at 120 ⁰ C mixture, optimum running performance while taking off or blowing of the melt consist , whereby finer and more uniform fibers are obtained in a particularly good yield than with conventional processes.

Even with conventional batches of glass-forming oxides, the content of FCjO ₃ in the starting batch can be increased to a proportion of at least 15 percent by weight by iron oxide-containing additives, whereby the advantages obtained according to the invention

be achieved.

Depending on the composition of the initial

iron oxide shed

permanent wedge of the aui dem / · _{Jn wünsdU} em

quantity produced ^ [° _{required to control} an output sense. For ^ PJ 'π ₁₅ Gew.chis-

mixed with «JJAdM v ^ _{dw den}

Percent of earth oxides for the mixture

Proportion of FeA '™ i "" ^ "» * at least 25 pounds, at least 20 weight _{g * ^ sjnkt auto} mat.sc:h 30 weight _percent and can not be processed

the proportion of ^earth . ^a ^ Ss should be _pr Dozent. The mixture under 5 weight, pr _{m h}

appropriate amount of ^addi ^ t? _h suitable for a simple case of doubt each ^S ^ ^ r jtlschmeiversuchen routine investigations in 1 .eg _{mk of fn.}

Claims (7)

I 815244 ι higher. Iron oxide content, in particular a suitable patent claim: clay, can be added, the iron oxide content of the melt depending on the intended use. 1. Heat and acid resistant mineral fiber can be fitted,
products made from common glass-forming oxides or 5 Minerals, especially natural clays, and Iron oxides, characterized by fine content of fusible iron oxides of
at least 18 percent by weight, in addition to varying amounts of SiO ₂ and Al ₂ O ₃ , optionally io customary admixtures and a proportion of up to The invention relates to heat-resistant and acid-resistant ru 5 percent by weight of alkaline earth and alkali mineral fiber products from common glass-forming oxides cxides, based on the weight of the at 12O ⁰ C or minerals, in particular natural clays, $ dried glass mix. and iron oxides and a process for their production 2. Heat and acid-resistant mineral fiber 15 position. Products according to claim 1, characterized by mineral wool, mineral fibers or the like. iteichnet that they are known from a starting mix of different composition. The fibers with more than 18 percent by weight, but at most, are generally up to temperature exposure 35 percent by weight of iron oxides produced from 500 to 600 ° C resistant. In this area lies is, the iron oxides from a mixture 20 also the limit of the application temperature. the of Fe ₂ O ₃ and FeO, possibly with low fire resistance of some special fibers, all- Fe ₃ O ₄ proportions exist and the mixture is well above these values. The LSA.- also 15 to 65 percent by weight SiO ₄ , 33 to patent specification 2,467,889 describes z. B. a mineral 12 percent by weight Al ₂ O ₃ and up to 5 weight fibers with a glazing temperature of 1100 C percent of a mixture of alkali and / or 45 has. The melting temperature is here Contains alkaline earth oxides. at about 1800 ° C. The use of such wool is 3. Heat and acid-resistant mineral fibers - but limited to certain special purposes, Products according to claim 1 and 2, made from they are referred to as special fibers, to which also a mixture that makes up 20 to 35 percent by weight of the quartz fiber wool. Contains iron oxides, the proportion of which consists of 30 The main mass of mineral fiber products from Fe ₂ O ₃ to FeO is over 5: 1, together with from SiO ₂ and Al ₂ O ₃ . Since these components have a 30 to »5 percent by weight SiO ₂ and about 25 to too high for most manufacturing processes 15 weight percent Al ₂ O ₃ . Must have melting point of glass-forming 4. Heat and acid-resistant mineral fiber mass, so-called fluxes are added, the products according to claim 1 to 3, made from 35 lower the melting temperature of the mixture, a mixture that is essentially as epoxides and the viscosity of the melt depending on only Fe borrowed _{Contains 2} O ₃ and FeO, the change influencing the temperature in such a way that fibers or the ratio of Fe ₂ O ₃ to FeO are in the range between 15: 1 wool or continuous filaments from the melt and about 25: 1. known drawing processes or blowing processes 5. Process for producing heat and acid 40 can be produced. Resistant mineral fiber products according to claim The fluxing agents used are in particular alkali oxides and 1 to 4, characterized in that known earth alkali auxides are used. They generally cause the melt to form a mixture of glass-forming, perfect flow behavior of the melt, require oxides with a high proportion, but at least affect the alkali and acid resistance but at least 18 percent by weight, based on the weight of the mineral fiber produced from the melt Glass batch dried at 120 C, products more or less »· disadvantageous. For this reason, iron oxides are used, and attempts have already been made to replace some of the alkali-known glass-forming oxides, in particular oxides and alkaline earth oxides, with iron oxides and aluminum, the iron being used. Such known mixtures always contain oxides essentially of Fe ₂ O ₃ and FeO in 50 over 5 percent by weight alkali oxides and / or earth ratio over 51, the usual alkali oxides, in addition to iron oxides, up to a maximum of 1% flux in the production of the melt. the iron oxides being used as flux or partially omitted, and the melt assigned only a supporting role; However, one of the known nozzle blowing processes has been blown away from processing iron oxide-containing into wool or abandoned again after one of the also 55 mixtures, because the iron oxides per se known drawing processes to fine threads increase the recrystallization tendency of the melt or continuous threads are pulled out and thus in the melting behavior unfavorable way 6. The method according to claim 5, characterized thereby · influencing. The use of alkali * and / or draws that an alkaline earth metal oxide as FhißmUteJ for the production of the melt, however, lowers the natural clay is used in which the βο application limit temperature of the fiber products and The required high proportion of iron oxides already reduces their resistance to acids. It now exists is included. a strong need for a mineral fiber, mineral » 7. The method according to claim S, characterized by wool or the like, the temperature and acid-resistant draws that for the production of the melt of and no disturbances in their production, z. B. a mixture of iron oxides and the per se «5 with regard to the tendency of the melt to recrystallize, known glass-forming oxides and / or minera * occur. lien is assumed, where appropriate, according to the invention, heat and acid or more glass-forming minerals with a permanent mineral fiber product proposed that